rickettsia

American  

[ri-ket-see-uh] / rɪˈkɛt si ə /

noun

plural

rickettsiae, rickettsias

1. any member of the genus Rickettsia, comprising rod-shaped to coccoid microorganisms that resemble bacteria but can be as small as a large virus and reproduce only inside a living cell, parasitic in fleas, ticks, lice, and mites and transmitted by bite to vertebrate hosts, including humans, causing such severe diseases as typhus and Rocky Mountain spotted fever.

2. any rickettsia or rickettsialike microorganism of the orders Rickettsiales and Chlamydiales.

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rickettsia British  

/ rɪˈkɛtsɪə /

noun

1. any of a group of parasitic bacteria that live in the tissues of ticks, mites, and other arthropods, and cause disease when transmitted to man and other animals

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Other Word Forms

• rickettsial adjective

Etymology

Origin of rickettsia

1915–20; < New Latin, after Howard T. Ricketts (1871–1910), U.S. pathologist; -ia